From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EE82215EFA2 for ; Mon, 1 Jul 2024 13:00:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719838821; cv=none; b=UO6r7xEjTqdM+sR3p4dxPpdYuI6em5Ok4cx9KlJeAYUqCu4WrhVHLwSAMjSvEH6SmU7yxp4ZyC8YoF8IkD5hVhrLjwdWLckGLySlKqEQqSFhxZd1JyzjYDnpEqnqwJ6BwG9Yg2XSJqsdRszCU3vUVmuI0Jh6sMW6gccIlraC7t8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719838821; c=relaxed/simple; bh=DU5Rpao9sVkwftxVXiBbPjmDCfg1edojbtuA+4rU99w=; h=MIME-Version:Date:In-Reply-To:Message-ID:Subject:From:To: Content-Type; b=bp5o0ssVDg/z8xJrZZGUNYNIV6QkH4ViH0n75tRPNRLRbw5wE1+3Jz6qc6QGJcLNZ9uqw971fB1uI/BYm+2xQDra4rMeVcjQl60FY8KSehTui+V2inETt2xkbON4ROxUGyjAT+y4zd8qd+Bxj27GrixuupsTmKsN+L3V56otgrw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f69.google.com with SMTP id ca18e2360f4ac-7f61fca8c40so313268839f.3 for ; Mon, 01 Jul 2024 06:00:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719838819; x=1720443619; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=lKQzMVVd8JV3z0u1HLRD129oSCr8seG4wu/QgPU2cjc=; b=YycqUOh3sA0gJseUtQp7F17FefOJX/EF9/7YWmEbM9ryZiEWnqFoFkqO6gRSbjpnyh 29OKG+t9ezDEJhE2v85qdgM+kIFMprVvrP4sSx+ahma5T8bXY5jOPbqMbH6ibaXTzyfd PWUbeSaPwat5eDf7erkGWPI2M+GRoxhiAVhpXfpTQJXJ+T3EKJLLpJaDS+Be46eGcQdr 4SG+CM5n+RShVKqWS4bmhpJht2nOCAIfqe9duJ4lFcmUVfk1+/lUIAtdDeRUM5tDvirI I9dSDTSSeiqtVJ8QPK11wl+dRsH1roTiW4amRWYeEFCo8777UrWZOBXyd+EDsxVOZwAn HSPA== X-Gm-Message-State: AOJu0Yxhqu/1fe/97Bu5HdKcALlZMWq+SV27v5BdvFzbwbplzcd7K8eM ElpPLRn/UD4g1OVmio6Cd0rZ5iQs+C+p2qPrnP13Xh7HrM4IskUGZo+qXBX2Bx6vtsGIe9hpevd fOchP+LQuwgALdaEFXPwloRXGStAnorg+c1VsCJ3flv2P7Rb7z6u7myM= X-Google-Smtp-Source: AGHT+IFjfzX64Rdy84nGXFpO+a/9DdmBFIA0Cb03XfztEfHdSopox7b2rYRLwMVVIk6xuXUnH0kqit7skKw8yR7UbffZUoOxCs2j Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6602:3f8a:b0:7eb:75e9:8f2b with SMTP id ca18e2360f4ac-7f62ee6461bmr43693339f.2.1719838819082; Mon, 01 Jul 2024 06:00:19 -0700 (PDT) Date: Mon, 01 Jul 2024 06:00:19 -0700 In-Reply-To: <0000000000006cbc570618c0d4a3@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000e1f1a9061c2f2d82@google.com> Subject: Re: [syzbot] [syzbot] [bpf?] [net?] KMSAN: uninit-value in dev_map_hash_lookup_elem From: syzbot To: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com. *** Subject: [syzbot] [bpf?] [net?] KMSAN: uninit-value in dev_map_hash_lookup_elem Author: wojciech.gladysz@infogain.com #syz test: https://linux.googlesource.com/linux/kernel/git/torvalds/linux e478cf26c556e4ab572ab0ab2306c986901dcd61 --- kernel/bpf/verifier.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 36ef8e96787e..13a9c2e2908a 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7146,8 +7146,8 @@ static int check_stack_range_initialized( * reads. However, if raw_mode is not set, we'll do extra * checks below. */ - bounds_check_type = BPF_WRITE; - clobber = true; + clobber = !meta || meta->raw_mode; + bounds_check_type = clobber ? BPF_WRITE : BPF_READ; } else { bounds_check_type = BPF_READ; } @@ -7230,8 +7230,7 @@ static int check_stack_range_initialized( stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE]; if (*stype == STACK_MISC) goto mark; - if ((*stype == STACK_ZERO) || - (*stype == STACK_INVALID && env->allow_uninit_stack)) { + if (*stype == STACK_ZERO) { if (clobber) { /* helper can write anything into the stack */ *stype = STACK_MISC; @@ -8748,6 +8747,8 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, meta->map_uid = reg->map_uid; break; case ARG_PTR_TO_MAP_KEY: + /* always mark read access */ + meta->raw_mode = false; /* bpf_map_xxx(..., map_ptr, ..., key) call: * check that [key, key + map->key_size) are within * stack limits and initialized @@ -8763,7 +8764,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, } err = check_helper_mem_access(env, regno, meta->map_ptr->key_size, false, - NULL); + meta); break; case ARG_PTR_TO_MAP_VALUE: if (type_may_be_null(arg_type) && register_is_null(reg)) -- 2.35.3